Sound-amplifier.



' K. B. HASTINGS..

SOUND AMPLIFIER. I APPLICATION FILED MAR. 10. 19W.

. Patented Nov. 13, 1917.

" 5 lmeva nsensitiveness of sound waves.

the transmitter UNITED STATES PATENT OFFICE.

KENNETH B. HASTINGS, 0F BOSTON,MASSACHUSETTS.

' sounn-Ai/irmrmn.

To all whom it may concern:

Be it known that I, 'KENNETH B. HAs- 'rrnos, a citizen of the United States, and resident of Boston, in the county of Suffolk and State of Massachusetts, have in vented an Improvement in Sound-Amplifiers, of which thefollowi'ng description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

My present invention is an improved sound accelerator for usein telephone transmitt'ers. The object of the invention is to improve and perfect sound concentrating or focusing apparatus for use in. connection with telephone instruments employed in aiding hearing, especially such as are portable and carried by the user. In the manufacture of this type of hearing aids it is extremelyimportant that any sound amplifyingdevice whichis employed, shall be very compact, light, attractive, and unobtrusive inappearance, because of the well-known deaf or partially deaf per sons to their affliction.

' "Heretofore it has been attempted to make sound concentrating devices for such telephone transmitters with some sort of encircling shell or resonators, to conduct the sound waves onto the diaphragm of the transmitter. Such prior devices, however,

afforded very little increase in efliciency and all of the same required the telephone diaphragm and transm'tter to be in a position opening away from the direction of the Furthermore, these prior devices depended upon a substantially rigid construction which tended to deadenor dissipate the sound waves while the same were being focused. Also a further difficulty was that such prior devices admitted extraneous and ob ectionable noises to a large degree. In my present device I have provided an improved arrangement of a rality of accelerators to concentrate, conduct andincrease the action of the sound waves whileleading the same onto" the center of diaphragm. These accelerators are preferably so sustainedas to permit a considerable vibration or spring which, in use, actually increases in a clear and sharp manner, the action of the sound waves. I also find that the usual extraneous and objectionable noises or rumbles are largely eliminated in the use of my amplifier. I account for this remarkable pheeated at 12 and'13.

Patented Nov. 13, 1917.

Application filed March 10, 191 7. Serial No. 153,985.

nomenon because of the fact that the direct 1 sound waves are considerably increased as they are led from one resonator or concentrator to another, thus actually seeming to increase the spoken words which constitute the main sound waves. the bell also clarifies the tone and dissipates the outside noises. a

' Referring to the drawings illustrating preferred embodiments of the invention,

p Fi re 1 is a rear plan view of my amplifying transmitter; and

Fig. 2 is a cross sectional view of the same.

"In the accompanying drawings I have illustrated a plurality of three sound concentrating devices, although the invention is fully carried out with a plurality of two such concentrating devices, and therefore I will first describe the transmitter as though fitted with the two'sound deflectors, the addition of the third being a modification,

which will be described later.

T he apparatus includes a transmitter, designated generally at 1, and shown in subs'tantially" conventional form with the diaphragm 2 thereon, carried by the box' 3, to

which is attached the cover 4 in usual manner, having an opening 5 therethrough arand 7 substantially as shown in Fig. 2 with a rounded sound deflecting portion 9. Attached to the rim of the outer flange por- 8 is a thin platelO having a downtion turned edge 11 arranged to fit over the'rim of the flange 8. This plate also has a plurality of perforations, preferably as indi- This plate is somewhat yielding and on its inner surface carries a bell-shaped member 14, which latter is of suitable diameter and extent whereby the rim 15 will extend over and slightly down into the slightly rounded portion 9 between the inner flange 7. and outer flange 8 of the member 6. The apparatus as thus de- The vibration of scribed when employed only with theflange 8and bell '14: is attached to the wearer or may be employed,

the transmitter carried by the suspension ring 16 attached to the back of the apparatus. In this position the diaphragm 52 faces the direction of the sound, which enters through the series of perforations l2 and 13, impinges against the Walls of the grooves 9 and from thence is deflected into the inner wall of the bellshaped member 14, reverberating back- Wardly and forwardly between the same and the cover 4 until reaching the ,opening 5. The bellmem benle beingsecured to thecenter of the plate 10 by the screw l6, permits both said plate and the bell member to vibrate somewhat and to act as a sounding board, amplifying, concentrating and focusing the sound waves through the central opening 5 and onto the diaphragm, and also clarifying the tone through the vibration of the bell member itself. Thus two distinct vibrations are secured, one through the vibration of the plate holding the bell and the other through the vibratory properties of the bell member itself.

The apparatus enablesa clear, sharp amplification of the sound waves to be directed onto the transmitter diaphragm, While the construction actually eliminates the objectionable rumbling noises through the action of the bell as explained above. :Theiseries of perforationsaroundthe front of theiplate 10 further accentuate the vibratory action of thep'late andbell, thus increasingthe soundingboard effect. d

If desired, an additional concentrator such as the cupshaped member 17, having its central portion.18

contacting with the plate 10 within the series of perforations and. also secured thereto by the'screw l6, and the outer rim of said member" 17 extending as an encircling shell 19 overlapping and covering the flange ,8, said shell having a curved peripheral form as illustrated at 20. With this additional attachment, the sound waves,.collecting and entering between the rim l9 and flange 8 are thrown by the curved wall 20 througli the perforations 12 and 13 and thence onwardlyto the transmitter 2 as has been described. lVith this additional magnifying attachment, the instrument may be carried or wornby the user in the same position as before, although I prefer to have the attachment 1'? opening outwardly, and for this purpose would remove the suspending ring 15 andattacli a similar ring 20 to the n upper part of, the cup-shaped member 17. In

either case the wiresQl and 22 could be led as shown inthe drawings.

My amplifying and clarifying combination, either with or without the attachment 17 gives a simple, eflicient and compact apparatus, which is arranged to receive, conduct, amplify and clarify, as well asfocus, the sound waves, upon the central portion of diaphragm. The elasticity which attachment and vibratory properties of the sound conductingflanges and members aids very materially in magnifying the action of the sounds upon the diaphragm of the transmitter. Furthermore, I find that the action of the transmitter brings out the sound waves with a clear, sharp and well defined tone, while almost entirely eliminating objectional noises. In fact, the magnifying and sharpness is so pronounced that Lmay employ advantageously-a much smaller diaphragm than has heretofore been believed possible, thereby increasing ,the sharpness of the tones transmitted and .enabling the entire apparatus to be compact and unobtrusive, as well as attractive in appearance. My invention is further describedand defined in the form of claims as follows:

1. Apparatus for. amplifyingsound, consisting in the combination of a telephone transmitter, a cover therefor having acentralopening for the transmitter diaphragm, a surrounding flange-,like member, of greater diameterthan the transmitter, and extending forwardly. thereof, having sound deflecting walls, a platecarried by the flangelike member, and provided with av plurality of openings around its periphery, said plate having a central bell-shaped member overlapping the transmitter cover, whereby sound waves entering said perforations are deflectedby the flange-like member to the bell-shaped memberand from thence .to the transmitter.

2. Apparatus for amplifying sound and focusing the sound waves upon the center of a telephone transmitter, comprising a transmitter, an encircling fiange like member eatending forwardly I of the transmitter, a ,plate carried bysaid flange-like member,

openings through said plate within the diameter'of the flange-like member, and, bellshaped member attached to the inner surface of the plate and opening toward the transmitter,said plateandbell-shaped member havinga Capacity vibration whereby said ,wavesentermg said perforat ons are deflected, concentrated and focused upon the telephone transmitter.

3. Apparatus for amplifying sound and focus ng the sound waves upon the center of a telephone transmitter,comprising a transber having a capacity for vibration, in comblllltlOIl with a concentrating attachment also carried by the said perforated plate, overlaps and is of greater diameter than said flanged member, whereby a plurality of sound concentrating members are provided.

4. Apparatus for amplifying sound and simultaneously clarifying the tone and focusing the sound waves upon a telephone transmitter, comprising the transmitter, and a flange-like member substantially encircling the transmitter, a bell-shaped member coopcrating with said flange-like member and a vibratory support for said bell-shaped member.

5. Apparatus for amplifying sound and simultaneously clarifying the tone and focusing the sound waves upon the, center of a telephone transmitter, comprising the Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G.

and concen- 

